Recently, winter tires often have been used not only on icy roads but also on dry roads. Thus, winter tires are requested to have not only sufficient on-ice performance but also an excellent steering stability and wear-resistance on dry roads.
In order to improve on-ice performance, a winter tire having a tread portion provided with a lot of sipes to offer edge effect has been proposed. Unfortunately, such a winter tire may deteriorate in steering performance on dry roads as well as wear resistance due to low rigidity of the tread portion. One of the related arts to the invention is as follows.